ZHCSI09S June 2010 – August 2018 TPS65911
GPIO0, GPIO2, GPIO6, and GPIO7 can be programmed to be part of the power-up sequence and used as enable signals for external resources.
GPIO0 is a configurable I/O in the VCC7 domain. By default, its output is push-pull, driving low. GPIO0 can also be configured as an open-drain output with external pullup.
GPIO1 through GPIO8 are configurable open-drain digital I/Os in the VRTC domain. GPIO directivity, debouncing delay, and internal pullup can be programmed. By default, all are inputs with weak internal pulldown; as open-drain output an external pullup is required.
GPIO0, GPIO1, and GPIO3 through GPIO5 can be used to turn on the device if the corresponding interrupt is not masked. When configured as an input, GPIO2 cannot be used to turn on the device, even if its associated interrupt is not masked. The GPIO interrupt is level sensitive. When an interrupt is detected, before clearing the interrupt, it should first be disabled by masking it.
GPIO1 and GPIO3, which have current sink capability of 10 mA, can also be used to drive LEDs connected to a 5-V supply.
GPIO2 can be used for synchronizing DC-DC converters to an external clock. Programming DCDCCKEXT = 1, VDD1, VDD2, and VIO DCDC switching can be synchronized using a 3-MHz clock set though the GPIO2 pin. VDD1 and VDD2 will be in-phase and VIO will be phase shifted by 180 degrees.
It is recommended not to connect noisy switching signals to GPIO4 and GPIO5.